networking/udhcp/common.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Rewrite by Russ Dill <Russ.Dill@asu.edu> July 2001
   4  *
   5  * Licensed under GPLv2, see file LICENSE in this source tree.
   6  */
   7 #include "common.h"
   8
   9 #if defined CONFIG_UDHCP_DEBUG && CONFIG_UDHCP_DEBUG >= 1
  10 unsigned dhcp_verbose;
  11 #endif
  12
  13 const uint8_t MAC_BCAST_ADDR[6] ALIGN2 = {
  14         0xff, 0xff, 0xff, 0xff, 0xff, 0xff
  15 };
  16
  17 #if ENABLE_UDHCPC || ENABLE_UDHCPD
  18 /* Supported options are easily added here.
  19  * See RFC2132 for more options.
  20  * OPTION_REQ: these options are requested by udhcpc (unless -o).
  21  */
  22 const struct dhcp_optflag dhcp_optflags[] = {
  23         /* flags                                    code */
  24         { OPTION_IP                   | OPTION_REQ, 0x01 }, /* DHCP_SUBNET        */
  25         { OPTION_S32                              , 0x02 }, /* DHCP_TIME_OFFSET   */
  26         { OPTION_IP | OPTION_LIST     | OPTION_REQ, 0x03 }, /* DHCP_ROUTER        */
  27 //      { OPTION_IP | OPTION_LIST                 , 0x04 }, /* DHCP_TIME_SERVER   */
  28 //      { OPTION_IP | OPTION_LIST                 , 0x05 }, /* DHCP_NAME_SERVER   */
  29         { OPTION_IP | OPTION_LIST     | OPTION_REQ, 0x06 }, /* DHCP_DNS_SERVER    */
  30 //      { OPTION_IP | OPTION_LIST                 , 0x07 }, /* DHCP_LOG_SERVER    */
  31 //      { OPTION_IP | OPTION_LIST                 , 0x08 }, /* DHCP_COOKIE_SERVER */
  32         { OPTION_IP | OPTION_LIST                 , 0x09 }, /* DHCP_LPR_SERVER    */
  33         { OPTION_STRING_HOST          | OPTION_REQ, 0x0c }, /* DHCP_HOST_NAME     */
  34         { OPTION_U16                              , 0x0d }, /* DHCP_BOOT_SIZE     */
  35         { OPTION_STRING_HOST          | OPTION_REQ, 0x0f }, /* DHCP_DOMAIN_NAME   */
  36         { OPTION_IP                               , 0x10 }, /* DHCP_SWAP_SERVER   */
  37         { OPTION_STRING                           , 0x11 }, /* DHCP_ROOT_PATH     */
  38         { OPTION_U8                               , 0x17 }, /* DHCP_IP_TTL        */
  39         { OPTION_U16                              , 0x1a }, /* DHCP_MTU           */
  40 //TODO: why do we request DHCP_BROADCAST? Can't we assume that
  41 //in the unlikely case it is different from typical N.N.255.255,
  42 //server would let us know anyway?
  43         { OPTION_IP                   | OPTION_REQ, 0x1c }, /* DHCP_BROADCAST     */
  44         { OPTION_IP_PAIR | OPTION_LIST            , 0x21 }, /* DHCP_ROUTES        */
  45         { OPTION_STRING_HOST                      , 0x28 }, /* DHCP_NIS_DOMAIN    */
  46         { OPTION_IP | OPTION_LIST                 , 0x29 }, /* DHCP_NIS_SERVER    */
  47         { OPTION_IP | OPTION_LIST     | OPTION_REQ, 0x2a }, /* DHCP_NTP_SERVER    */
  48         { OPTION_IP | OPTION_LIST                 , 0x2c }, /* DHCP_WINS_SERVER   */
  49         { OPTION_U32                              , 0x33 }, /* DHCP_LEASE_TIME    */
  50         { OPTION_IP                               , 0x36 }, /* DHCP_SERVER_ID     */
  51         { OPTION_STRING                           , 0x38 }, /* DHCP_ERR_MESSAGE   */
  52 //TODO: must be combined with 'sname' and 'file' handling:
  53         { OPTION_STRING_HOST                      , 0x42 }, /* DHCP_TFTP_SERVER_NAME */
  54         { OPTION_STRING                           , 0x43 }, /* DHCP_BOOT_FILE     */
  55 //TODO: not a string, but a set of LASCII strings:
  56 //      { OPTION_STRING                           , 0x4D }, /* DHCP_USER_CLASS    */
  57 #if ENABLE_FEATURE_UDHCP_RFC3397
  58         { OPTION_DNS_STRING | OPTION_LIST         , 0x77 }, /* DHCP_DOMAIN_SEARCH */
  59         { OPTION_SIP_SERVERS                      , 0x78 }, /* DHCP_SIP_SERVERS   */
  60 #endif
  61         { OPTION_STATIC_ROUTES | OPTION_LIST      , 0x79 }, /* DHCP_STATIC_ROUTES */
  62 #if ENABLE_FEATURE_UDHCP_8021Q
  63         { OPTION_U16                              , 0x84 }, /* DHCP_VLAN_ID       */
  64         { OPTION_U8                               , 0x85 }, /* DHCP_VLAN_PRIORITY */
  65 #endif
  66         { OPTION_STRING                           , 0xd1 }, /* DHCP_PXE_CONF_FILE */
  67         { OPTION_STRING                           , 0xd2 }, /* DHCP_PXE_PATH_PREFIX */
  68         { OPTION_6RD                              , 0xd4 }, /* DHCP_6RD           */
  69         { OPTION_STATIC_ROUTES | OPTION_LIST      , 0xf9 }, /* DHCP_MS_STATIC_ROUTES */
  70         { OPTION_STRING                           , 0xfc }, /* DHCP_WPAD          */
  71
  72         /* Options below have no match in dhcp_option_strings[],
  73          * are not passed to dhcpc scripts, and cannot be specified
  74          * with "option XXX YYY" syntax in dhcpd config file.
  75          * These entries are only used internally by udhcp[cd]
  76          * to correctly encode options into packets.
  77          */
  78
  79         { OPTION_IP                               , 0x32 }, /* DHCP_REQUESTED_IP  */
  80         { OPTION_U8                               , 0x35 }, /* DHCP_MESSAGE_TYPE  */
  81         { OPTION_U16                              , 0x39 }, /* DHCP_MAX_SIZE      */
  82 //looks like these opts will work just fine even without these defs:
  83 //      { OPTION_STRING                           , 0x3c }, /* DHCP_VENDOR        */
  84 //      /* not really a string: */
  85 //      { OPTION_STRING                           , 0x3d }, /* DHCP_CLIENT_ID     */
  86         { 0, 0 } /* zeroed terminating entry */
  87 };
  88
  89 /* Used for converting options from incoming packets to env variables
  90  * for udhcpc script, and for setting options for udhcpd via
  91  * "opt OPTION_NAME OPTION_VALUE" directives in udhcpd.conf file.
  92  */
  93 /* Must match dhcp_optflags[] order */
  94 const char dhcp_option_strings[] ALIGN1 =
  95         "subnet" "\0"      /* DHCP_SUBNET         */
  96         "timezone" "\0"    /* DHCP_TIME_OFFSET    */
  97         "router" "\0"      /* DHCP_ROUTER         */
  98 //      "timesrv" "\0"     /* DHCP_TIME_SERVER    */
  99 //      "namesrv" "\0"     /* DHCP_NAME_SERVER    */
 100         "dns" "\0"         /* DHCP_DNS_SERVER     */
 101 //      "logsrv" "\0"      /* DHCP_LOG_SERVER     */
 102 //      "cookiesrv" "\0"   /* DHCP_COOKIE_SERVER  */
 103         "lprsrv" "\0"      /* DHCP_LPR_SERVER     */
 104         "hostname" "\0"    /* DHCP_HOST_NAME      */
 105         "bootsize" "\0"    /* DHCP_BOOT_SIZE      */
 106         "domain" "\0"      /* DHCP_DOMAIN_NAME    */
 107         "swapsrv" "\0"     /* DHCP_SWAP_SERVER    */
 108         "rootpath" "\0"    /* DHCP_ROOT_PATH      */
 109         "ipttl" "\0"       /* DHCP_IP_TTL         */
 110         "mtu" "\0"         /* DHCP_MTU            */
 111         "broadcast" "\0"   /* DHCP_BROADCAST      */
 112         "routes" "\0"      /* DHCP_ROUTES         */
 113         "nisdomain" "\0"   /* DHCP_NIS_DOMAIN     */
 114         "nissrv" "\0"      /* DHCP_NIS_SERVER     */
 115         "ntpsrv" "\0"      /* DHCP_NTP_SERVER     */
 116         "wins" "\0"        /* DHCP_WINS_SERVER    */
 117         "lease" "\0"       /* DHCP_LEASE_TIME     */
 118         "serverid" "\0"    /* DHCP_SERVER_ID      */
 119         "message" "\0"     /* DHCP_ERR_MESSAGE    */
 120         "tftp" "\0"        /* DHCP_TFTP_SERVER_NAME */
 121         "bootfile" "\0"    /* DHCP_BOOT_FILE      */
 122 //      "userclass" "\0"   /* DHCP_USER_CLASS     */
 123 #if ENABLE_FEATURE_UDHCP_RFC3397
 124         "search" "\0"      /* DHCP_DOMAIN_SEARCH  */
 125 // doesn't work in udhcpd.conf since OPTION_SIP_SERVERS
 126 // is not handled yet by "string->option" conversion code:
 127         "sipsrv" "\0"      /* DHCP_SIP_SERVERS    */
 128 #endif
 129         "staticroutes" "\0"/* DHCP_STATIC_ROUTES  */
 130 #if ENABLE_FEATURE_UDHCP_8021Q
 131         "vlanid" "\0"      /* DHCP_VLAN_ID        */
 132         "vlanpriority" "\0"/* DHCP_VLAN_PRIORITY  */
 133 #endif
 134         "pxeconffile" "\0" /* DHCP_PXE_CONF_FILE  */
 135         "pxepathprefix" "\0" /* DHCP_PXE_PATH_PREFIX  */
 136         "ip6rd" "\0"       /* DHCP_6RD            */
 137         "msstaticroutes""\0"/* DHCP_MS_STATIC_ROUTES */
 138         "wpad" "\0"        /* DHCP_WPAD           */
 139         ;
 140 #endif
 141
 142 /* Lengths of the option types in binary form.
 143  * Used by:
 144  * udhcp_str2optset: to determine how many bytes to allocate.
 145  * xmalloc_optname_optval: to estimate string length
 146  * from binary option length: (option[LEN] / dhcp_option_lengths[opt_type])
 147  * is the number of elements, multiply it by one element's string width
 148  * (len_of_option_as_string[opt_type]) and you know how wide string you need.
 149  */
 150 const uint8_t dhcp_option_lengths[] ALIGN1 = {
 151         [OPTION_IP] =      4,
 152         [OPTION_IP_PAIR] = 8,
 153 //      [OPTION_BOOLEAN] = 1,
 154         [OPTION_STRING] =  1,  /* ignored by udhcp_str2optset */
 155         [OPTION_STRING_HOST] = 1,  /* ignored by udhcp_str2optset */
 156 #if ENABLE_FEATURE_UDHCP_RFC3397
 157         [OPTION_DNS_STRING] = 1,  /* ignored by both udhcp_str2optset and xmalloc_optname_optval */
 158         [OPTION_SIP_SERVERS] = 1,
 159 #endif
 160         [OPTION_U8] =      1,
 161         [OPTION_U16] =     2,
 162 //      [OPTION_S16] =     2,
 163         [OPTION_U32] =     4,
 164         [OPTION_S32] =     4,
 165         /* Just like OPTION_STRING, we use minimum length here */
 166         [OPTION_STATIC_ROUTES] = 5,
 167         [OPTION_6RD] =    12,  /* ignored by udhcp_str2optset */
 168         /* The above value was chosen as follows:
 169          * len_of_option_as_string[] for this option is >60: it's a string of the form
 170          * "32 128 ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff 255.255.255.255 ".
 171          * Each additional ipv4 address takes 4 bytes in binary option and appends
 172          * another "255.255.255.255 " 16-byte string. We can set [OPTION_6RD] = 4
 173          * but this severely overestimates string length: instead of 16 bytes,
 174          * it adds >60 for every 4 bytes in binary option.
 175          * We cheat and declare here that option is in units of 12 bytes.
 176          * This adds more than 60 bytes for every three ipv4 addresses - more than enough.
 177          * (Even 16 instead of 12 should work, but let's be paranoid).
 178          */
 179 };
 180
 181
 182 #if defined CONFIG_UDHCP_DEBUG && CONFIG_UDHCP_DEBUG >= 2
 183 static void log_option(const char *pfx, const uint8_t *opt)
 184 {
 185         if (dhcp_verbose >= 2) {
 186                 char buf[256 * 2 + 2];
 187                 *bin2hex(buf, (void*) (opt + OPT_DATA), opt[OPT_LEN]) = '\0';
 188                 bb_error_msg("%s: 0x%02x %s", pfx, opt[OPT_CODE], buf);
 189         }
 190 }
 191 #else
 192 # define log_option(pfx, opt) ((void)0)
 193 #endif
 194
 195 unsigned FAST_FUNC udhcp_option_idx(const char *name, const char *option_strings)
 196 {
 197         int n = index_in_strings(option_strings, name);
 198         if (n >= 0)
 199                 return n;
 200
 201         {
 202                 char *buf, *d;
 203                 const char *s;
 204
 205                 s = option_strings;
 206                 while (*s)
 207                         s += strlen(s) + 1;
 208
 209                 d = buf = xzalloc(s - option_strings);
 210                 s = option_strings;
 211                 while (!(*s == '\0' && s[1] == '\0')) {
 212                         *d++ = (*s == '\0' ? ' ' : *s);
 213                         s++;
 214                 }
 215                 bb_error_msg_and_die("unknown option '%s', known options: %s", name, buf);
 216         }
 217 }
 218
 219 /* Get an option with bounds checking (warning, result is not aligned) */
 220 uint8_t* FAST_FUNC udhcp_get_option(struct dhcp_packet *packet, int code)
 221 {
 222         uint8_t *optionptr;
 223         int len;
 224         int rem;
 225         int overload = 0;
 226         enum {
 227                 FILE_FIELD101  = FILE_FIELD  * 0x101,
 228                 SNAME_FIELD101 = SNAME_FIELD * 0x101,
 229         };
 230
 231         /* option bytes: [code][len][data1][data2]..[dataLEN] */
 232         optionptr = packet->options;
 233         rem = sizeof(packet->options);
 234         while (1) {
 235                 if (rem <= 0) {
 236  complain:
 237                         bb_error_msg("bad packet, malformed option field");
 238                         return NULL;
 239                 }
 240
 241                 /* DHCP_PADDING and DHCP_END have no [len] byte */
 242                 if (optionptr[OPT_CODE] == DHCP_PADDING) {
 243                         rem--;
 244                         optionptr++;
 245                         continue;
 246                 }
 247                 if (optionptr[OPT_CODE] == DHCP_END) {
 248                         if ((overload & FILE_FIELD101) == FILE_FIELD) {
 249                                 /* can use packet->file, and didn't look at it yet */
 250                                 overload |= FILE_FIELD101; /* "we looked at it" */
 251                                 optionptr = packet->file;
 252                                 rem = sizeof(packet->file);
 253                                 continue;
 254                         }
 255                         if ((overload & SNAME_FIELD101) == SNAME_FIELD) {
 256                                 /* can use packet->sname, and didn't look at it yet */
 257                                 overload |= SNAME_FIELD101; /* "we looked at it" */
 258                                 optionptr = packet->sname;
 259                                 rem = sizeof(packet->sname);
 260                                 continue;
 261                         }
 262                         break;
 263                 }
 264
 265                 if (rem <= OPT_LEN)
 266                         goto complain; /* complain and return NULL */
 267                 len = 2 + optionptr[OPT_LEN];
 268                 rem -= len;
 269                 if (rem < 0)
 270                         goto complain; /* complain and return NULL */
 271
 272                 if (optionptr[OPT_CODE] == code) {
 273                         log_option("option found", optionptr);
 274                         return optionptr + OPT_DATA;
 275                 }
 276
 277                 if (optionptr[OPT_CODE] == DHCP_OPTION_OVERLOAD) {
 278                         if (len >= 3)
 279                                 overload |= optionptr[OPT_DATA];
 280                         /* fall through */
 281                 }
 282                 optionptr += len;
 283         }
 284
 285         /* log3 because udhcpc uses it a lot - very noisy */
 286         log3("option 0x%02x not found", code);
 287         return NULL;
 288 }
 289
 290 /* Return the position of the 'end' option (no bounds checking) */
 291 int FAST_FUNC udhcp_end_option(uint8_t *optionptr)
 292 {
 293         int i = 0;
 294
 295         while (optionptr[i] != DHCP_END) {
 296                 if (optionptr[i] != DHCP_PADDING)
 297                         i += optionptr[i + OPT_LEN] + OPT_DATA-1;
 298                 i++;
 299         }
 300         return i;
 301 }
 302
 303 /* Add an option (supplied in binary form) to the options.
 304  * Option format: [code][len][data1][data2]..[dataLEN]
 305  */
 306 void FAST_FUNC udhcp_add_binary_option(struct dhcp_packet *packet, uint8_t *addopt)
 307 {
 308         unsigned len;
 309         uint8_t *optionptr = packet->options;
 310         unsigned end = udhcp_end_option(optionptr);
 311
 312         len = OPT_DATA + addopt[OPT_LEN];
 313         /* end position + (option code/length + addopt length) + end option */
 314         if (end + len + 1 >= DHCP_OPTIONS_BUFSIZE) {
 315 //TODO: learn how to use overflow option if we exhaust packet->options[]
 316                 bb_error_msg("option 0x%02x did not fit into the packet",
 317                                 addopt[OPT_CODE]);
 318                 return;
 319         }
 320         log_option("adding option", addopt);
 321         memcpy(optionptr + end, addopt, len);
 322         optionptr[end + len] = DHCP_END;
 323 }
 324
 325 #if ENABLE_UDHCPC || ENABLE_UDHCPD
 326 /* Add an one to four byte option to a packet */
 327 void FAST_FUNC udhcp_add_simple_option(struct dhcp_packet *packet, uint8_t code, uint32_t data)
 328 {
 329         const struct dhcp_optflag *dh;
 330
 331         for (dh = dhcp_optflags; dh->code; dh++) {
 332                 if (dh->code == code) {
 333                         uint8_t option[6], len;
 334
 335                         option[OPT_CODE] = code;
 336                         len = dhcp_option_lengths[dh->flags & OPTION_TYPE_MASK];
 337                         option[OPT_LEN] = len;
 338                         if (BB_BIG_ENDIAN)
 339                                 data <<= 8 * (4 - len);
 340                         /* Assignment is unaligned! */
 341                         move_to_unaligned32(&option[OPT_DATA], data);
 342                         udhcp_add_binary_option(packet, option);
 343                         return;
 344                 }
 345         }
 346
 347         bb_error_msg("can't add option 0x%02x", code);
 348 }
 349 #endif
 350
 351 /* Find option 'code' in opt_list */
 352 struct option_set* FAST_FUNC udhcp_find_option(struct option_set *opt_list, uint8_t code)
 353 {
 354         while (opt_list && opt_list->data[OPT_CODE] < code)
 355                 opt_list = opt_list->next;
 356
 357         if (opt_list && opt_list->data[OPT_CODE] == code)
 358                 return opt_list;
 359         return NULL;
 360 }
 361
 362 /* Parse string to IP in network order */
 363 int FAST_FUNC udhcp_str2nip(const char *str, void *arg)
 364 {
 365         len_and_sockaddr *lsa;
 366
 367         lsa = host_and_af2sockaddr(str, 0, AF_INET);
 368         if (!lsa)
 369                 return 0;
 370         /* arg maybe unaligned */
 371         move_to_unaligned32((uint32_t*)arg, lsa->u.sin.sin_addr.s_addr);
 372         free(lsa);
 373         return 1;
 374 }
 375
 376 /* udhcp_str2optset:
 377  * Parse string option representation to binary form and add it to opt_list.
 378  * Called to parse "udhcpc -x OPTNAME:OPTVAL"
 379  * and to parse udhcpd.conf's "opt OPTNAME OPTVAL" directives.
 380  */
 381 /* helper for the helper */
 382 static char *allocate_tempopt_if_needed(
 383                 const struct dhcp_optflag *optflag,
 384                 char *buffer,
 385                 int *length_p)
 386 {
 387         char *allocated = NULL;
 388         if ((optflag->flags & OPTION_TYPE_MASK) == OPTION_BIN) {
 389                 const char *end;
 390                 allocated = xstrdup(buffer); /* more than enough */
 391                 end = hex2bin(allocated, buffer, 255);
 392                 if (errno)
 393                         bb_error_msg_and_die("malformed hex string '%s'", buffer);
 394                 *length_p = end - allocated;
 395         }
 396         return allocated;
 397 }
 398 /* helper: add an option to the opt_list */
 399 static NOINLINE void attach_option(
 400                 struct option_set **opt_list,
 401                 const struct dhcp_optflag *optflag,
 402                 char *buffer,
 403                 int length)
 404 {
 405         struct option_set *existing;
 406         char *allocated;
 407
 408         allocated = allocate_tempopt_if_needed(optflag, buffer, &length);
 409 #if ENABLE_FEATURE_UDHCP_RFC3397
 410         if ((optflag->flags & OPTION_TYPE_MASK) == OPTION_DNS_STRING) {
 411                 /* reuse buffer and length for RFC1035-formatted string */
 412                 allocated = buffer = (char *)dname_enc(NULL, 0, buffer, &length);
 413         }
 414 #endif
 415
 416         existing = udhcp_find_option(*opt_list, optflag->code);
 417         if (!existing) {
 418                 struct option_set *new, **curr;
 419
 420                 /* make a new option */
 421                 log2("attaching option %02x to list", optflag->code);
 422                 new = xmalloc(sizeof(*new));
 423                 new->data = xmalloc(length + OPT_DATA);
 424                 new->data[OPT_CODE] = optflag->code;
 425                 new->data[OPT_LEN] = length;
 426                 memcpy(new->data + OPT_DATA, (allocated ? allocated : buffer), length);
 427
 428                 curr = opt_list;
 429                 while (*curr && (*curr)->data[OPT_CODE] < optflag->code)
 430                         curr = &(*curr)->next;
 431
 432                 new->next = *curr;
 433                 *curr = new;
 434                 goto ret;
 435         }
 436
 437         if (optflag->flags & OPTION_LIST) {
 438                 unsigned old_len;
 439
 440                 /* add it to an existing option */
 441                 log2("attaching option %02x to existing member of list", optflag->code);
 442                 old_len = existing->data[OPT_LEN];
 443                 if (old_len + length < 255) {
 444                         /* actually 255 is ok too, but adding a space can overlow it */
 445
 446                         existing->data = xrealloc(existing->data, OPT_DATA + 1 + old_len + length);
 447                         if ((optflag->flags & OPTION_TYPE_MASK) == OPTION_STRING
 448                          || (optflag->flags & OPTION_TYPE_MASK) == OPTION_STRING_HOST
 449                         ) {
 450                                 /* add space separator between STRING options in a list */
 451                                 existing->data[OPT_DATA + old_len] = ' ';
 452                                 old_len++;
 453                         }
 454                         memcpy(existing->data + OPT_DATA + old_len, (allocated ? allocated : buffer), length);
 455                         existing->data[OPT_LEN] = old_len + length;
 456                 } /* else, ignore the data, we could put this in a second option in the future */
 457         } /* else, ignore the new data */
 458
 459  ret:
 460         free(allocated);
 461 }
 462
 463 int FAST_FUNC udhcp_str2optset(const char *const_str, void *arg, const struct dhcp_optflag *optflags, const char *option_strings)
 464 {
 465         struct option_set **opt_list = arg;
 466         char *opt, *val;
 467         char *str;
 468         const struct dhcp_optflag *optflag;
 469         struct dhcp_optflag bin_optflag;
 470         unsigned optcode;
 471         int retval, length;
 472         /* IP_PAIR needs 8 bytes, STATIC_ROUTES needs 9 max */
 473         char buffer[9] ALIGNED(4);
 474         uint16_t *result_u16 = (uint16_t *) buffer;
 475         uint32_t *result_u32 = (uint32_t *) buffer;
 476
 477         /* Cheat, the only *const* str possible is "" */
 478         str = (char *) const_str;
 479         opt = strtok(str, " \t=");
 480         if (!opt)
 481                 return 0;
 482
 483         optcode = bb_strtou(opt, NULL, 0);
 484         if (!errno && optcode < 255) {
 485                 /* Raw (numeric) option code */
 486                 bin_optflag.flags = OPTION_BIN;
 487                 bin_optflag.code = optcode;
 488                 optflag = &bin_optflag;
 489         } else {
 490                 optflag = &optflags[udhcp_option_idx(opt, option_strings)];
 491         }
 492
 493         retval = 0;
 494         do {
 495                 val = strtok(NULL, ", \t");
 496                 if (!val)
 497                         break;
 498                 length = dhcp_option_lengths[optflag->flags & OPTION_TYPE_MASK];
 499                 retval = 0;
 500                 opt = buffer; /* new meaning for variable opt */
 501                 switch (optflag->flags & OPTION_TYPE_MASK) {
 502                 case OPTION_IP:
 503                         retval = udhcp_str2nip(val, buffer);
 504                         break;
 505                 case OPTION_IP_PAIR:
 506                         retval = udhcp_str2nip(val, buffer);
 507                         val = strtok(NULL, ", \t/-");
 508                         if (!val)
 509                                 retval = 0;
 510                         if (retval)
 511                                 retval = udhcp_str2nip(val, buffer + 4);
 512                         break;
 513                 case OPTION_STRING:
 514                 case OPTION_STRING_HOST:
 515 #if ENABLE_FEATURE_UDHCP_RFC3397
 516                 case OPTION_DNS_STRING:
 517 #endif
 518                         length = strnlen(val, 254);
 519                         if (length > 0) {
 520                                 opt = val;
 521                                 retval = 1;
 522                         }
 523                         break;
 524 //              case OPTION_BOOLEAN: {
 525 //                      static const char no_yes[] ALIGN1 = "no\0yes\0";
 526 //                      buffer[0] = retval = index_in_strings(no_yes, val);
 527 //                      retval++; /* 0 - bad; 1: "no" 2: "yes" */
 528 //                      break;
 529 //              }
 530                 case OPTION_U8:
 531                         buffer[0] = bb_strtou32(val, NULL, 0);
 532                         retval = (errno == 0);
 533                         break;
 534                 /* htonX are macros in older libc's, using temp var
 535                  * in code below for safety */
 536                 /* TODO: use bb_strtoX? */
 537                 case OPTION_U16: {
 538                         uint32_t tmp = bb_strtou32(val, NULL, 0);
 539                         *result_u16 = htons(tmp);
 540                         retval = (errno == 0 /*&& tmp < 0x10000*/);
 541                         break;
 542                 }
 543 //              case OPTION_S16: {
 544 //                      long tmp = bb_strtoi32(val, NULL, 0);
 545 //                      *result_u16 = htons(tmp);
 546 //                      retval = (errno == 0);
 547 //                      break;
 548 //              }
 549                 case OPTION_U32: {
 550                         uint32_t tmp = bb_strtou32(val, NULL, 0);
 551                         *result_u32 = htonl(tmp);
 552                         retval = (errno == 0);
 553                         break;
 554                 }
 555                 case OPTION_S32: {
 556                         int32_t tmp = bb_strtoi32(val, NULL, 0);
 557                         *result_u32 = htonl(tmp);
 558                         retval = (errno == 0);
 559                         break;
 560                 }
 561                 case OPTION_STATIC_ROUTES: {
 562                         /* Input: "a.b.c.d/m" */
 563                         /* Output: mask(1 byte),pfx(0-4 bytes),gw(4 bytes) */
 564                         unsigned mask;
 565                         char *slash = strchr(val, '/');
 566                         if (slash) {
 567                                 *slash = '\0';
 568                                 retval = udhcp_str2nip(val, buffer + 1);
 569                                 buffer[0] = mask = bb_strtou(slash + 1, NULL, 10);
 570                                 val = strtok(NULL, ", \t/-");
 571                                 if (!val || mask > 32 || errno)
 572                                         retval = 0;
 573                                 if (retval) {
 574                                         length = ((mask + 7) >> 3) + 5;
 575                                         retval = udhcp_str2nip(val, buffer + (length - 4));
 576                                 }
 577                         }
 578                         break;
 579                 }
 580                 case OPTION_BIN: /* handled in attach_option() */
 581                         opt = val;
 582                         retval = 1;
 583                 default:
 584                         break;
 585                 }
 586                 if (retval)
 587                         attach_option(opt_list, optflag, opt, length);
 588         } while (retval && (optflag->flags & OPTION_LIST));
 589
 590         return retval;
 591 }
 592
 593 /* note: ip is a pointer to an IPv6 in network order, possibly misaliged */
 594 int FAST_FUNC sprint_nip6(char *dest, /*const char *pre,*/ const uint8_t *ip)
 595 {
 596         char hexstrbuf[16 * 2];
 597         bin2hex(hexstrbuf, (void*)ip, 16);
 598         return sprintf(dest, /* "%s" */
 599                 "%.4s:%.4s:%.4s:%.4s:%.4s:%.4s:%.4s:%.4s",
 600                 /* pre, */
 601                 hexstrbuf + 0 * 4,
 602                 hexstrbuf + 1 * 4,
 603                 hexstrbuf + 2 * 4,
 604                 hexstrbuf + 3 * 4,
 605                 hexstrbuf + 4 * 4,
 606                 hexstrbuf + 5 * 4,
 607                 hexstrbuf + 6 * 4,
 608                 hexstrbuf + 7 * 4
 609         );
 610 }